1. Field of the Invention
This invention pertains generally to devices adapted to being mounted on the wheels of a vehicle to improve traction on slippery surfaces and, more particularly, to an apparatus which can be installed and removed without raising or moving the vehicle and which can easily be adjusted to fit a variety of sizes of vehicle wheels.
2. Description of the Background Art
Various devices have been developed for installation on the wheels of a vehicle to improve traction on slippery surfaces. For example, U.S. Pat. No. 3,249,143 issued to Scott on May 3, 1966 discloses a traction device for mounting on vehicle tires without jacking the vehicle. It comprises arms extending from the wheel axis and radially spaced around the tire. The portion of the arm which extends to the tire surface is offset to extend around the tire surface. The arms are adjustable to account for spacing differences. Once installed and the arms are extended, a cover plate is attached over the wheel hub to lock the arms into position.
U.S. Pat. No. 4,886,100 issued to Parker, III on Dec. 12, 1989 discloses an anti-skid device adapted to be mounted on vehicle tires comprising hooks which fit around the surface of the tire. The hooks are attached to arms which extend over the outside of the tire and which are held in place by a ring chain. In addition, the hooks can be fitted with cleats, studs and other devices to increase traction on snow and ice.
German Patent No. 2,262,011 issued to Gomez on Dec. 19, 1972 discloses a traction device for vehicle tires having cleats spaced radially along the surface of the tire and connected to arms which are connected to a centrifugal hub. The arms rotate in guides when the tire spins and tighten the cleats against the tire surface.
U.S. Pat. No. 3,935,891 issued to McCloud et al. on Feb. 3, 1976 discloses a traction device for vehicle tires which generally comprises a clamping device mounted on the tire and having a gripping surface on the outer periphery, an adapter plate to which the clamping device is attached, and an optional extension which adds traction surface to the device. The adapter plate is mounted on the wheel of the vehicle and a plurality of clamping devices are attached to the adapter plate, the same being evenly spaced around the tire. The clamping device can have various types of gripping surfaces ranging from cleated plates to studs.
U.S. Pat. No. 4,089,359 issued to Jones on May 16, 1978 discloses an assembly mounted on a vehicle tire which comprises a plurality of arms extending radially from the center of the tire to the outer surface, the ends of which have cleats which wrap around the surface of the tire. The arms to which the cleats are attached are telescoping for proper positioning.
U.S. Pat. No. 2,598,851 issued to Spevak on Jun. 3, 1952 discloses an emergency traction device which generally comprises a circular plate attached to the wheel of a vehicle and "L" shaped brackets which are in turn attached to the circular plate and extend over the surface of the tire.
U.S. Pat. No. 3,045,738 issued to Lombardi on Jul. 24, 1962 discloses a traction device which comprises a circular hub which attached to the wheel of a vehicle and which has "finger brackets" to which "L" shaped clamping brackets containing cleats are attached.
U.S. Pat. No. 3,151,654 issued to Minutilla on Oct. 6, 1964 discloses a traction devise comprising a plurality of radially disposed arms which are adjustable to the size of the tire so that they firmly grip the tire adjacent to the road surface but will expand as they leave the road surface.
U.S. Pat. No. 3,117,612 issued to Minutilla on Jan. 14, 1964 discloses a traction device which has radially spaced cleats which are locked and retained at high speeds by using centrifugal force to lock them in their guide channels.
U.S. Pat. No. 4,278,122 issued to Vagias on Jul. 14, 1981 discloses a traction device comprising a circular hub to which a plurality of traction fingers on supporting shanks are attached and which are equally spaced around the tire.
The foregoing patents reflect the state of the art of which the applicant is aware and are tendered with the view toward discharging applicant's acknowledged duty of candor in disclosing information which may be pertinent in the examination of this application. It is respectfully stipulated, however, that none of these patents teach or render obvious, singly or when considered in combination, applicant's claimed invention.